Notice that the pattern is "previous term plus 2". This is an arithmetic sequence where the difference (d) equals +2
= a₁ + d(n - 1) ; where a₁ is the first term, d is the difference, and n is the term.
f(n) = 1 + 2(n - 1)
f(n) = 1 + 2n - 2
f(n) = 2n - 1
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f(10) = 2(10) - 1
f(10) = 20 - 1
f(10) = 19
To find the best deal find the unit rate.
City express unit rate for pants per dollars is 1 pair : $20.33
Denim Planet unit rate is 1 pair : $36.50
New Threads Unit rate is 1 pair : $27.50
So City Express is the best deal
The answer is D. The slope is 5 and (2, 4) is on the line.
<span>Simplifying
3a2 + -2a + -1 = 0
Reorder the terms:
-1 + -2a + 3a2 = 0
Solving
-1 + -2a + 3a2 = 0
Solving for variable 'a'.
Factor a trinomial.
(-1 + -3a)(1 + -1a) = 0
Subproblem 1Set the factor '(-1 + -3a)' equal to zero and attempt to solve:
Simplifying
-1 + -3a = 0
Solving
-1 + -3a = 0
Move all terms containing a to the left, all other terms to the right.
Add '1' to each side of the equation.
-1 + 1 + -3a = 0 + 1
Combine like terms: -1 + 1 = 0
0 + -3a = 0 + 1
-3a = 0 + 1
Combine like terms: 0 + 1 = 1
-3a = 1
Divide each side by '-3'.
a = -0.3333333333
Simplifying
a = -0.3333333333
Subproblem 2Set the factor '(1 + -1a)' equal to zero and attempt to solve:
Simplifying
1 + -1a = 0
Solving
1 + -1a = 0
Move all terms containing a to the left, all other terms to the right.
Add '-1' to each side of the equation.
1 + -1 + -1a = 0 + -1
Combine like terms: 1 + -1 = 0
0 + -1a = 0 + -1
-1a = 0 + -1
Combine like terms: 0 + -1 = -1
-1a = -1
Divide each side by '-1'.
a = 1
Simplifying
a = 1Solutiona = {-0.3333333333, 1}</span>
So if you subtract the 0 out from the left side, the equation is now
. Since a x is common in both of the terms on the left side, you can factor it out, now making the equation look like
. When factoring, each of the separate things (x and (x-3)), must equal zero while the other one doesn't matter. So in order for the equation to be 0, the only potential options for x is 0 and 3. Therefore x=0 and x=3 are the two solutions
